Ticketing is an essential function in public transportation networks. A ticketing function must successfully address several key requirements from both the traveler's and the operator's perspectives. Typical traveler requirements may include ease of use (easy to learn and routine in practice), clear and visible pricing, secure with respect to loss, theft, or forgery, e.g., ticket books, passes, etc., and privacy preserving. Typical operator requirements of a ticketing function may include user acceptance (barriers to usage can quickly lead to a rejection of the transportation system by the public), security (confidentiality of the transaction, authentication, and non-repudiation, fraud resistance (amateur and organized)), and high availability. Additional requirements of the operator to ticketing functions will correspond to deployment costs, both for infrastructure (readers, validation systems, personnel, etc.) and mobility (tickets, cards, etc., in the hands of the traveler).
Near field communications (“NFC”) is a set of standards for smartphones and similar portable user devices to establish radio communication with each other by touching them together or bringing them into close proximity, e.g., a few centimeters. The short-range wireless technologies employed in NFC operations typically require a distance of 10 cm or less. NFC requires an initiator and a target, with the initiator capable of actively generating an RF field that can power a passive target or communicate with an active target. This arrangement allows for the use of targets having a very simplistic form, such as tags, key fobs, stickers, cards, etc., which do not require batteries. NFC tags may be read-only or rewriteable, and may be custom encoded. NFC tags may be configured to provide various communication speeds, memory, and security, write endurance, etc. In some instances, the target may include a power source, e.g., NFC peer-to-peer communications. Examples of NFC enabled techniques are disclosed in U.S. Patent Application Publication No. 2014/0201066 to Pascal Roux et al, which published on Jul. 17, 2014 and is incorporated herein by reference in its entirety.